Question

1....workout (5×7)-(8×4)
2...[1 feet = 12 inches] change 100 inches into feet.
3...workout 0.8×300
4.....if 3x-7 =17,what is the value of x?
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Answer 1

Answer:

1.)  3

2.) 8 1/3 feet or 8.3 feet ( answer rounded to the nearest tenths )

3.) 240

4.) 8

Step-by-step explanation:

1.) According to PEMDAS ( parenthesis, exponents, multiplication, division, addition, subtraction ) we need to solve whats in the the parenthesis first:

5*7= 35

8*4=32

Then, we need to subtract the two products:

35-31=3

2.) To turn feet into inches, you need to multiply the number of feet by 12, but to turn inches to feet, you need to divide the number of inches by 12. So, you need to take the number of inches ( 100 inches ) and divide it by 12:

100/12=8 1/3 feet or 8.3 feet ( answer rounded to the nearest tenths )

3.) For this problem, you want to multiply the two numbers how you would multiply any other two whole numbers and its important to realize that you don't need to line up the decimal points:

( Check the bottom for how to show your work for the multiplication or, if you don't need to show work, you can run the numbers through a calculator)

4.) Since we're trying to solve for a variable, we need to work in reverse and do the opposite of what we would usually do. Since we would subtract last, we're going to add first. So, you need to add 7 instead of subtracting 7 to both sides and you should be left with:

3x=24

The next thing we need to do is divide by 3 on both sides to find the value of x. When we divide by 3 on both sides, we're left with:

x= 8

Work for number 3: